Ion exchangers in wastewater reclamation.

Item Type Thesis-Reproduction (electronic); text

Authors Campos-Saravia, Oscar Vicente,1942-

Publisher The University of Arizona.

Rights Copyright © is held by the author. Digital access to this materialis made possible by the University Libraries, University of Arizona.Further transmission, reproduction or presentation (such aspublic display or performance) of protected items is prohibitedexcept with permission of the author.

Download date 19/06/2018 04:40:57

Link to Item http://hdl.handle.net/10150/191552

ION EXCHANGERS IN WASTEWATER RECLAMATION

by

Oscar Vicente Campos-Saravia

A Thesis Submitted to the Faculty of the

DEPARTMENT OF CIVIL ENGINEERING AND ENGINEERING MECHANICS

In Partial Fulfillment of the RequirementsFor the Degree of

MASTER OF SCIENCEWITH A MAJOR IN CIVIL ENGINEERING

In the Graduate College

THE UNIVERSITY OF ARIZONA

1971

This thesis has been approved on the date shown below:

lo /V/ ROBERT A. PHILLIPS Date

Professor of Civil Engineering

SIGNED:

STATEMENT BY AUTHOR

This thesis has been submitted in partial fulfillment of re-quirements for an advanced degree at The University of Arizona and isdeposited in the University Library to be made available to borrowersunder rules of the Library.

Brief quotations from this thesis are allowable without specialpermission, provided that accurate acknowledgment of source is made.Requests for permission for extended quotation from or reproduction ofthis manuscript in whole or in part may be granted by the head of themajor department or the Dean of the Graduate College when in his judg-ment the proposed use of the material is

/ in the interests of scholar-

ship. In all other instances, however, ipermissl,o@must be obtainedfrom the author.

APPROVAL BY THESIS DIRECTOR

ACKNOWLEDGMENTS

The author wishes to express his sincere gratitude to Dr.

Robert A. Phillips for his advice and guidance in the preparation of

this thesis. Professor Quentin M. Mees is to be thanked for his sug-

gestions concerning the subject matter of this thesis. The Department

of Civil Engineering and Engineering Mechanics, The University of Ari-

zona, must be credited for providing the necessary facilities.

The author also wishes to thank the Nalco Chemical Company and

the Rohm and Haas Company for providing the resins and their necessary

information. Appreciation is extended to other members of the faculty,

staff, and fellow students for their comments and suggestions.

Mrs. J. L. Cude is to be thanked for typing this thesis.

TABLE OF CONTENTS

LIST OF ILLUSTRATIONS

LIST OF TABLES

ABSTRACT

CHAPTER

INTRODUCTION

Purpose and Scope

1

1

II REVIEW OF LITERATURE 3

Characteristics of an Oxidation Pond Effluent . . 3Ion Exchange Process 3

Ion Exchange Resins 4Resin Properties 4

Capacity 4Regeneration 5Backwashing 5Other Operating Conditions 5

Previous Investigations 6

III EXPERIMENTAL TECHNIQUES AND ANALYSES 9

Preliminary Waste Water Clarification 9Resin Techniques 9

Experimental Apparatus 9Resin Characteristics 11

Dowex HGR-W 11Amberlite XE-258 11Dowex 11 13

Column Operation 13Analyses 13

IV DATA PRESENTATION AND DISCUSSION 15

Phase 1. Operation Without Organic Screen • • . • 15Phase 2. Operation With Organic Screen 31Application for Industrial Needs 47

Operating Cost 48

Page

vi

viii

ix

iv

V

TABLE OF CONTENTS--Continued

CHAPTER Page

V SUMMARY AND CONCLUSIONS 53

APPENDIX A: SUGGESTED OPERATING CONDITIONS FOR RESINS USED . 55

APPENDIX B: RESULTS OF ANALYSES PERFORMED DURING PHASE 1AND PHASE 2 59

REFERENCES 70

-

LIST OF ILLUSTRATIONS

Figure Page

1. Characteristics of the Filter Sand 10

2. Diagram of the Demineralizing System 12

3. pH Readings During Phase 1 18

4. Specific Conductance Readings During Phase 1 . . . 19

5. Alkalinity Results During Phase 1 20

6. Total Hardness Results During Phase 1 21

7. Turbidity Results During Phase 1 23

8. Total Residue Analyses During Phase 1 24

9. Total Filterable Residue Analyses During Phase 1 . . 25

10. Oxygen Absorption Results During Phase 1 26

U. COD Results During Phase 1 27

12. MBAS Results During Phase 1 28

13. Calcium Results During Phase 1 29

14. Chloride Results During Phase 1 30

15. pH Readings During Phase 2 32

16. Specific Conductance Readings During Phase 2 . . • • 33

17. Alkalinity Results During Phase 2 34

18. Total Filterable Residue Analyses During Phase 2 35

19. Oxygen Absorption Results During Phase 2 36

20. COD Results During Phase 2 37

21. MBAS Results During Phase 2 38

vi

Figure

LIST OF ILLUSTRATIONS--Continued

.

vii

Page

22. Sodium Results During Phase 2 39

23. Chloride Results During Phase 2 40

24. pH Readings After Dowex 11 Resin 41

25. Specific Conductance Readings After Dowex 11Resin 42

26. Alkalinity Results After Dowex 11 Resin 43

27. COD Results After Dowex 11 Resin 44

28. Chloride Results After Dowex 11 Resin 45

LIST OF-TABLES

Table Page

1. Quality of treated oxidation pond effluent forcolumn loading (Phase 1)

16

2. Quality of treated oxidation pond effluent forcolumn loading (Phase 2) 17

3. Comparison between the suggested limits oftolerance for boiler feed waters and the waterobtained during this study 49

4. Comparison between the requirements for textilemanufacture waters and the water obtained during

this study 50

vi ii

ABSTRACT

The effluent of a sewage oxidation pond owned and operated by

Pima County, Arizona, and located near Tucson, Arizona, was used to

evaluate the feasibility of the use of the ion exchange process for

treatment of waters of this type. The oxidation pond effluent was

pretreated with alum, settled, and filtered.

When Dowex HGR-W and Amberlite XE-258 resins were used in a

conventional system, the quality of the effluent water decreased dur-

ing subsequent cycles as did the original capacity of the system. With

the installation of Dowex 11 anion resin ahead of the other two, better

quality water was obtained and original capacity of the system retained

during successive cycles.

ix

CHAPTER I

INTRODUCTION

Over the last two decades new sources of water have been a sub-

ject of many conferences, meetings, investigations, etc. Undoubtedly,

this subject is important especially in areas where shortages of water

exist. It has been demonstrated in areas where the agricultural, in-

dustrial, commercial, and domestic water supply is by ground water that

water levels of these sources are being depleted at high rates. Simi-

lar shortages are encountered with surface supplies as well.

One of the more promising sources of water is waste water from

communities. This represents 55 to 75 percent of the total water used.

Effluents from waste treatment plants and oxidation ponds can be im-

proved with proper treatment, and high quality water can be obtained.

The easiest and most logical step for treatment of an effluent

from an oxidation pond is a standard water treatment process, which in-

volves chemical dosage, mixing, flocculation, sedimentation, and fil-

tration, followed, perhaps, by a tertiary treatment. The choice for

this last step would be the one or more steps required to produce a de-

sired water depending on the quality requirements.

Purpose and Scope

In addition to standard water treatment, tertiary treatment by

ion exchange process was selected for the purpose of this thesis. The

1

2

objective of this research was to evaluate the pond effluent after

treatment by both processes, and ascertain its possible application

for various industrial needs.

A modification in the ion exchange process was used to obtain

better quality water, longer periods of time between regenerations,

and consequently lower overall costs.

In order to accomplish the previously stated purposes, chemical

dosage, mixing, flocculation, sedimentation, and filtration were used

to remove algae and other particulate constituents from the oxidation

pond effluent. Following this treatment, demineralizing ion exchange

resins were employed. Laboratory analyses were conducted to evaluate

the potential value of the new water.

CHAPTER II

REVIEW OF LITERATURE

Sewage oxidation ponds are shallow basins used for purifying

waste water. These ponds are designed for detention periods of between

three and four weeks, using a biochemical oxygen demand (BOD) loading

in the vicinity of 45 lb/day/acre (1). Oxidation ponds are constructed

between three and four feet deep and have free form.

Characteristics of an OxidationPond Effluent

Sewage effluent from an oxidation pond can be used successfully

as irrigation water. It may increase crop yield and contributes nitro-

gen and other nutrients to the soil (2). For other purposes the degree

of treatment of the effluent from an oxidation pond depends on its

chemical composition and the potential use of the water.

Ion Exchange Process

Ion exchange can be defined as a reversible exchange of ions

between a solid and a liquid in which there is no substantial change

in the structure of the solid. In this definition the "solid" is the

ion exchange material Or resin particle (3).

During the past ten years, ion exchange techniques have found

wide application in the fields of water and waste water treatment. It

now can be compared with processes such as distillation and

3

4

precipitation for the removal of only certain undesirable components or

to produce extremely pure water.

Ion Exchange Resins

The most important ion exchange resins produced and employed

today are the synthetic organic resins. These synthetic ion exchange

resins are actually a special type of polyelectrolyte. Cross-linked

polyelectrolytes can be visualized as an elastic three-dimensional

hydrocarbon network. The most useful hydrocarbon network developed to

date is that formed by the copolymerization of styrene and divinyl-

benzene (3).

The chemical behavior of ion exchange resins is divided into

two major classes: 1) cation resins, those capable of exchanging

cations or positively charged ions; and 2) anion resins, those capable

of exchanging anions or negatively charged ions 3).

The nature of the ionizable groups attached to the hydrocarbon

network determines the chemical behavior of an ion exchange resin.

There are four major types of ion exchange resins in commercial use at

the present time: 1) strong acid (cation) resins, 2) weak acid

(cation) resins, 3) strong base (anion) resins, and 4) weak base

(anion) resins. The terms cation and anion refer to the charge on the

ions which are removed or exchanged.

Resin Properties

Capacity. The total capacity of an ion exchange resin is the

number of ionic (or potentially ionic) sites per unit weight or volume

5

of resin. The exchange capacity of a bed is commonly expressed in the

number of kilograins of substance removed from the liquid by passage

through 1 cu ft of exchange medium. Because ion exchangers were first

used for the softening of water, comparisons of exchange capacity are

generally made by expressing the substance removed in terms of hardness

as CaCO3'

A more useful unit of exchange capacity is the number of

gram-equivalents of ions removed by a unit volume of exchanger. Gram-

equivalents per kilogram or milliequivalents per gram may be used in-

stead. Capacity curves for individual resins are provided by manufac-

turers.

Regeneration. When a bed is no longer capable of useful ion

exchange, it is said to be exhausted and needs regeneration. The re-

generating requirements of a bed are expressed in pounds of chemical

per cubic foot of exchanger or per kilograin of substance removed from

the liquid.

Backwashing. The backwashing process for ion exchange resins

is based on the principle used for backwashing sand filters. The flow

rate is expressed in gpm/sq ft. Another way for expressing flow rate

is based on the backwash flow required for a desired percent expansion

of the resin. Expression of flow rates varies according to the operat-

ing conditions suggested by the manufacturers. The flow is upward and

washes off light insoluble contaminants. Backwashing also eliminates

resin compaction.

Other Operating Conditions. The pH range, maximum temperature,

minimum bed depth, service flow rate, rinse water requirements, and

6

other operating conditions for each resin are provided in guides from

the manufacturers.

Previous Investigations

Today in almost all ion exchange processes synthetic organic

resins are being used. These synthetic organic resins at first were

limited to the cationic type and were used extensively for water

softening.

In about 1948, strong basic anion exchange resins were devel-

oped. These resins are more difficult to manufacture and have a lower

chemical and thermal stability than the cation resins (4).

The largest and oldest application of ion exchange resins is in

water treatment. Of the 680,000 cu ft of resins produced in 1961, it

is estimated that 600,000 cu ft went to water treatment (5). Cation

resins are used for the removal of hardness and partial alkalization

of water, whereas both anion and cation resins are required for demin-

eralization. Other special applications which use anion exchange

resins include the removal of sulfates, hydrogen sulfides, and nitrates

from water.

In 1960, it was estimated that there were 1500 technical arti-

cles published on ion exchange resins (6). Klumb (7) has referred to

the biological fouling in which the resins are clumped together by bac-

teria and because of this clumping are not free to exchange their ions

or to be regenerated. He also pointed out that experimental evidence

indicates that cation exchangers are incapable in themselves of sus-

taining bacterial growth. Bacteria may grow in the softener material

7

because of the presence of filtered organic matter, especially during

optimum temperature conditions (7). .

Wirth (8) has reported that chlorine present in the water is

primarily responsible for cation resin degradation. Iron and manganese

cause inorganic fouling, principally to the cation resins, and periodic

cleanup procedures are recommended to remove these fouling agents. In-

organic ions have also been reported as a source of fouling for anion

resins but this is considered to be a minor cause (8).

The largest quantities of anion exchange resins are used in de-

mineralization of water supplies. Associated with their use are prob-

lems of resin deterioration and fouling. Many researchers have attrib-

uted this deterioration and fouling to four main causes: 1) biological

fouling, 2) chemical attack, 3) inorganic fouling, and 4) organic

fouling. This fouling is so serious that 25 percent of the annual sales

of anion resins are for the replacement of fouled or deteriorated res-

ins (9).

One of the main reasons for organic fouling of anion exchange

resins is due to the exchange of large amounts of organic acids. Ac-

cumulation of these acids on the resins gradually reduces the operat-

ing capacity of the column. The most important technique in prevention

of fouling is the limiting of organic accumulation on the resins. The

use of scavenger beds appears to be an effective means of fouling pre-

vention (10).

Recent studies (11) have shown that special strong base anion

exchange resins can be installed ahead of a demineralizing system to

8

screen out organics responsible for poisoning anionic resins. This al-

lows for longer periods of time between regenerations and in increasing

the lifetime of the resins.

CHAPTER III

EXPERIMENTAL TECHNIQUES AND ANALYSES

Preliminary Waste Water Clarification

Samples of waste water were obtained from the Ina Road oxida-

tion pond, Pima County, Arizona. Solids were removed by batch clari-

fication in 50-gal drums using a dosage to 450 mg/1 alum [as Al 2 (SO4 ) 3 *

18 H20] followed by an adjustment to pH 6 + 0.1. The optimum pH range

for coagulation with alum is between 5.0 to 7.0. Below pH 5.0 the al-

kalinity is insufficient to precipitate Al3+

completely, and above pH

7.0 the tendency is for aluminate ions to be formed which will dissolve

(12).

Times of 60 sec, 30 min, and 2 hr were used for rapid mixing,

flocculation, and sedimentation, respectively. The clarified superna-

tant was withdrawn by a siphon and filtered through a 2.5-ft, gravel-

supported sand filter at a rate of 3 gpm/sq ft. The effective size of

the sand was 0.49 mm, with a uniformity coefficient of 1.59, as shown

in Figure 1.

Resin Techniques

Experimental Apparatus

In the first phase of this study, a strong acid cation exchange

resin (Dowex HGR-W), followed by a strongly basic anion exchange resin

(Amberlite XE-258), was employed. The second phase of the study

9

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involved the use of a second strongly basic anion exchange resin (Dowex

11), which was installed ahead of the two previously mentioned resins,

as shown in Figure 2.

Lucite columns of 1.25-in , diameter and 18-in , height were

filled with the resin material to a depth of 12 in., giving a volume

of 0.00836 cu ft. Backwashing of the resin was done by attaching a

second column to the top of the resin columns in order to provide

needed expansion height.

Resin Characteristics

Dowex HGR-W. This cation exchange resin is produced from a

sulfonated copolymer of styrene and 10 percent divinylbenzene. For de-

ionization Dowex HGR-W in combination with strong base resins can pro-

vide extremely high purity water. Suggested operating conditions in

the hydrogen cycle (13), as provided by the manufacturer, are presented

in Appendix A.

Amberlite XE-258. This anion exchange resin derives its ex-

change activity from guaternary ammonium groups. The difference be-

tween this resin and the styrene-divinylbenzene resins is that the

acrylic-based structure is more hydrophilic. Laboratory tests have

suggested that Amberlite XE-258 resin can be used as an organic scav-

enger in the treatment of waters (10), and in the hydroxide form can

be used as the anion exchanger component of a conventional deioniza-

tion system. Suggested operating conditions for Amberlite XE-258

(Rohm and Haas Company, Philadelphia, Pennsylvania) in the hydroxyl

form are presented in Appendix A.

12

13

Dowex 11. This is a high porosity strong base anion exchange

resin. Its porous structure offers advantages in treating waters which

contain organic matter and color. Suggested operating conditions in

the hydroxyl form (13) are presented in Appendix A.

Column Operation

Regeneration levels of 9.5 lb Na0H/cu ft and concentrations of

4 percent NaOH were used to provide a capacity of 18 Kgr/cu ft as CaCO3

in the anion exchangers (13). For the cation exchanger a regenerant

level of 9 lb H25O

4/cu ft and a concentration of 96 percent

H2SO4

was

used to provide it with a capacity of 20 Kgr/cu ft as CaCO 3 (13).

Backwash, regeneration, and rinse steps were carried out at

equivalent rates and volumes as recommended by the resin manufacturers

and are presented in Appendix A.

Analyses

Water quality tests used in evaluating resin performance were

carried out according to "Standard Methods" (14) with the exception of

the oxygen absorption test (3). This test was used as a mean of eval-

uating the organic matter at levels below the lower limits of sensitiv-

ity for the chemical oxygen demand (COD) test.

Oxygen absorption (OA) values are expressed as mg/1 of oxygen

just as in the COD test. The OA values do not necessarily have a con-

stant relationship to values obtained by means of the COD test. The OA

method uses the weaker oxidizing agent potassium permanganate rather

than potassium dichromate and was carried out for 4 hr at 27°C.

14

The following analyses were conducted for evaluating raw water

quallty and resin performance:

Analysis Method

Hydrogen ion concentration (pH) Glass electrode pH meter

Specific conductance Conductivity meter

Turbidity Jackson candle turbidimeter andspectrophotometer

Alkalinity Potentiometric titration method

Residue (total and filterable) Residue on evaporation

Total hardness EDTA titration method

Oxygen absorption (OA Acid permanganate method

Chemical oxygen demand (COD) Dichromate reflux method

Methylene blue active sub- Chloroform extractionstance (MBAS)

CHAPTER IV

DATA PRESENTATION AND DISCUSSION

As stated in Chapter III, Phase 1 of this study dealt with the

use of a cation exchange resin (Dowex HGR-W) and an anion exchange

resin (Amberlite XE-258) installed in series. Phase 2 involved the use

of a second anion exchange resin (Dowex 11) acting as an organic screen

and installed ahead of the above two resins.

The effluent of the stabilization lagoon was treated as previ-

ously described. Tables 1 and 2 show the characteristics of the influ-

ent water used during Phase 1 and Phase 2 of this study, respectively.

Phase 1. Operation Without Organic Screen

The procedure in this phase was to submit the two resins to

four operating cycles. Following exhaustion, backwashing, regeneration,

and rinse, each cycle was repeated. Samples for analyses were taken

every 30 min (except for total residue and total filtrable residue which

were taken every 60 min) after the cycle started and until the system

was not able to remove any ions, or the concentration of these ions in

the effluent increased considerably (exhaustion symptoms).

Figures 3, 4, 5, and 6 show the variations in pH, specific con-

ductance, total alkalinity, and total hardness for the four consecutive

operating cycles. During these cycles, pH, specific conductance, and

total alkalinity values were nearly constant during the first 270 min,

15

16

Table 1. Quality of treated oxidation pond effluent for column loading(Phase 1).

OxidationAnalyses Pond

Effluent

EffluentAfter AlumCoagulation

EffluentAfter

Filtration

pH 7.6 6.0 6.5

Temperature, °C 16 18 20

Turbidity, JTU 163 26 15

Specific conductance, umhos 660 880 900

Total residue, mg/1 774 843 872

Filterable residue, mg/1 645 804 835

Alkalinity, mg/1 as CaCO 3 375 146 146

Total hardness, mg/1 as CaCO 3 168 168 160

Calcium, mg/1 - 58

Chloride, mg/1 157

Oxygen-absorption, mg/1 5.72 5.0 4.7

COD, mg/1 247 53.6 39.5

MBAS, mg/1 435 2.00 1.72

17

Table 2. Quality of treated oxidation pond effluent for column loading(Phase 2).

OxidationAnalyses Pond

Effluent

EffluentAfter

Coagulation

Effluent AfterFiltration

a b

pH 7.5 6.0 6.3 7.05

0Temperature, C 16 27 24 14

Turbidity, JTU 145 33 19 17

Specific conductance,umhos

780 900 970 780

Total residue, mg/1 629 629 620 -

Filterable residue, mg/1 529 594 603 534

Alkalinity, mg/1 asCaCO

3315 116 115 130

Total hardness, mg/1 as 126 128 146 167.2CaCO

3

Calcium, mg/1 - - 48 53

Chloride, mg/1 - 124 127.1

Sodium, mg/1 - - 190 185

Oxygen absorption, mg/1 6.32 5.4 5.0 -

COD, mg/1 294 59.8 51.2 45.1

MBAS, mg/1 7.5 4.15 3.0 -

a. Average quality of influent during first cycle.

b. Average quality of influent during second cycle.

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after which they rose to a maximum value at around 390 min. Thereafter

they decreased sharply with a tendency to reach values for the alum

clarified effluent. Total hardness ions, which were absent before 360

min during the first three cycles, appeared at about 330 min during the

fourth cycle.

Figures 7, 8, and 9 show the variations in turbidity, total

residue, and total filterable residue analyses during Phase 1. These

values which also remained nearly constant during the first 270 min in-

creased after this time and almost reached values for the influent

water.

Organic matter, as expressed by OA and COD tests, was low during

the first 270 min of Phase 1, increasing sharply after this period of

time, as shown in Figures 10 and 11. Methylene blue active substance

(MBAS) was not detectable before 390 min during the first cycle; how-

ever, during the successive cycles it was detected sooner as can be

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haustion.

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started to occur at approximately 270 min after the cycle started.

Results of these analyses increased or were detected sooner during the

successive cycles (Figures 3 through 12) indicating a decrease in the

original capacity of the system and possible shorter periods of time

between regenerations.

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Phase 2. Operation With Organic Screen

The procedure in this phase consisted of the installation of a

new anionic resin (Dowex 11) ahead of the system used in Phase 1. As

indicated by Horembala and Feldt (11), Dowex 11 has been shown to be

effective in removing (scavenging) organic matter and hence prolonging

the lifetime of anionic exchange resins.

Effluent samples were taken every 30 min (except for total

residue and total filterable residue which were taken every 60 min)

during the entire cycle. After approximately 600 min, changes indicat-

ing that the anion exchangers were becoming exhausted were observed in

most tests. The cycle operation was ended after 840 min. The resins

were regenerated as previously described, and the process was repeated

for a second cycle of 840 min. Figures 15 through 23 show the results

of analyses performed during the two operating cycles of Phase 2.

Samples for analyses taken after the alum-clarified effluent

passed through the Dowex 11 resin were also conducted for the purpose of

evaluating its performance. The results of these analyses can be ob-

served in Tables 10 and 12 of Appendix B and in Figures 24 through 28.

Figures 15, 16, and 17 show the results for pH, specific con-

ductance, and alkalinity during the entire two cycles of Phase 2. In

both cycles, for the first 240 min, values of these parameters gave

very similar results. At that time the capacity of the cation exchange

resin began to diminish and the leakage of cations increased. The in-

crease continued for about 60 min after which the cation exchange resin

was completely exhausted.

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After 240 min, the concentration of hydroxide ions in the ef-

fluent rose, causing the pH, specific conductance, and alkalinity to

increase. After 300 min, when the cation exchange resin was considered

to be exhausted, the values became more stable until a greater amount

of leakage started to be detected in the anionic exchangers. This

greater amount of leakage occurred at approximately 600 min and was the

beginning of exhaustion for the anion exchange resins.

The results for the second phase showed a greater removal of

ions than during the first cycle. If organic poisoning of the resins

were occurring, one would expect that the reverse would be true--that

capacity would be reduced. Since this did not occur it appears that

the addition of the Dowex 11 ahead of the other two resins was effec-

tive in preventing fouling. In this case, however, there should have

been no change rather than the improved capacity found. This incon-

sistency is perhaps due to side wall effect in the columns, uneven dis-

tribution of the flow through the columns, or the original conversion

of the resin to the proper ionic form.

Total filterable residue analyses remained very low for the

first 240 min of both cycles (Figure 18). An increase in total filter-

able residue occurred when cation exchange resin was beginning to ex-

haust. Afterwards, these results became more stable for as long as the

anion exchange resins show no exhausting symptoms.

Organic matter analyses determined by the OA and COD tests

(Figures 19 and 20) showed very low residuals for the first 600 min,

47

indicating that anion exchange resins were mainly responsible for this

removal.

Concentrations of MBAS were almost identical during the two

operating cycles (Figure 21) and did not appear before 480 min in

either cycle. Residuals of these substances started to appear when the

anion exchange resin was decreasing in capacity and increasing in leak-

age.

Sodium and chloride analyses (Figures 22 and 23), which were

indicators of the performance of the system throughout the entire oper-

ation, gave almost identical results during both cycles. This was an

indication that the column operation was retaining the original capac-

ity.

Dowex 11 installed ahead of the other two resins proved to

maintain its original capacity and properties since no indication of

fouling was observed (Figures 24 through 28). There is no doubt that

during the two cycles of this phase much lower concentrations were ob-

tained among the different components analyzed, showing that the per-

formance of a demineralizing system can be improved with longer column

paths and proper protection for fouling agents. Concentrations of

these components analyzed did not have a tendency to increase during

the second cycle as happened with successive cycles of Phase 1.

Application for Industrial Needs

The ideal quality of water required for industrial use varies

widely for the many purposes to which water is put. Needless to

say, it is impossible to organize the quality requirements of the

water used for each of the many different industrial processes

into a single set of standards. Such quality requirements differ

48

far too much to allow any broad generalization or simplifi-cation. Within any industrial plant, water may have severalfunctions, the quality requirements for which vary markedly(5, p. 250).

In general, industries are willing to accept for most processes

water that meets drinking water standards. Where water of higher qual-

ity is required, industries must rely upon appropriate in-plant treat-

ment.

The quality of the water obtained in this study meets most of

the suggested limits of tolerance for waters intended for general in-

dustrial uses. Among the different industrial uses where the water ob-

tained might be used, only two applications will be mentioned in this

thesis. Tables 3 and 4 show the comparison between the suggested

limits for boiler feed waters and textile manufacture water with water

obtained during this experiment.

Operating Cost

With the installation of the Dowex 11 resin ahead of the demin-

eralizer, it was possible to increase the operating cycle from 300 min

to 660 min. At this time, exhaustion started in the anion exchange

resins, causing the concentration of anionic ions to increase and reach

values similar to those of the influent water.

An operating cycle was assumed to be that period of time before

a sharp reduction in the quality of the effluent was observed. For the

purpose of this study, 660 min was considered the service time for the

operating cycles of Phase 2.

49

Table 3. Comparison between the suggested limits of tolerance forboiler feed waters and the water obtained during thisstudy. *

Boiler Feed Water (15) A

Pressure, psi 0-150 150-250 250-400

Turbidity, JTU 20 10 5 1

Hardness as CaCO3

80 40 10 0

Bicarbonate as CaCO3

41 24.5 4.1 5

Carbonate as CaCO3

333 166 66 52

Hydroxyl as CaCO3 147 117 88 29

Total solids 3000-500 2500-500 1500-100 135

pH value (minimum) 8.0 8.4 9.0 9.9

Units are in mg/1 except for those specified.

A-Water obtained during this study.

50

Table 4. Comparison between the requirements for textile manufacturewaters and the water obtained during this study. *

AnalysesRequirements for

Textile Manufacture Water(15)

Water ObtainedDuring This Study

Turbidity, JTU 0.3-25 1

Color 0-70

Hardness 0-50 0

COD 15 14.2

Calcium 10 0

Magnesium 5 0

Sulfate 100

Chloride 100 6.5

Bicarbonate 200 9

*Units are in mg/1 except for those specified.

51

Operating costs for ion exchange processes are limited princi-

pally to the quantity of chemicals used in the process. The cost of

chemicals per unit volume of water treated is almost directly propor-

tional to the amount of mineral removed. In demineralization by ion

exchange resins, the amount of solids present in the feed water is a

dominant factor since the cost of chemicals could reach prohibitive

figures.

Ahlgren (16) has estimated that total costs per ion exchange

treatment of water with a total filterable residue level similar to

those in this study are approximately $1.10/1000 gal. He has also

shown that the chemical cost for waters with total filterable residue

(mg/1 as CaCO3 ) of 100, 250, and 500 can be treated for $0.13, $0.35,

and $0.70 per 1000 gal, respectively. The calculated chemical treat-

ment cost for water used in this study was $0.36/1000 gal at total

filterable residue values of about 600 mg/l. This assumes a cost for

sulfuric acid of 1.7c/lb and caustic soda of 3.3c/lb (17). The calcu-

lation for chemical treatment was done as follows:

Volume of resin: 8.36 x 10-3 cu ft

Time: 660 min

Flow rate: 2 gpm/cu ft

Chemical cost: 2(8.36 x 10-3 ) x 660 min x 2 22.07 gal

16.72 x 10-3

cu ft x 1000 gal- 0.757 cu ft

22.07 gal

9 lb/cu ft x 1.7c/lb x 0.757 cu ft = 11.68c/1000 gal

9.5 lb/cu ftx3.3c/lbx 0.757 cu ft = 23.92

11.68c/1000 gal + 23.92c/1000 gal 35.60c/1000 gal

52

It should be noted that neither overhead and maintenance nor

capital recovery are included in the computations. Cost for the dis-

posal of liquid wastes generated by backwashing, regeneration, and

rinse steps should be also considered according to the feasibility of

disposal.

CHAPTER V

SUMMARY AND CONCLUSIONS

Ion exchange treatment of coagulated and filtered sewage oxi-

dation pond effluent produced a water of high quality provided that

steps are taken to prevent damage to the resins because of fouling by

organic matter.

The utilization of the ion exchange demineralizing process for

upgrading and reuse of waste waters has been seriously hampered because

of the relatively high organic content of the water. Recently devel-

oped anion exchange resins such as Dowex 11 have been demonstrated to

be effective as organic scavengers, preventing deterioriation in the

capacity of the no ial resins used.

A combination of two resins, Dowex HGR-W and Amberlite XE-258,

such as might be used in a demineralizing process, have shown to have

their initial capacity reduced during subsequent operating cycles.

This reduction in capacity has been attributed to the deterioriation

of the cation resin and to the fouling of the anion resin.

Deterioriation of the cation exchange resin was due to the wide

variety of suspended matter present in the influent water and to the

filtering action that this resin was performing. The anion exchange

resin which was operated in the hydroxyl cycle also showed a decrease

in its original capacity after the first operating cycle. This loss in

capacity was shown by the greater concentration of detergents and

53

54

organic matter found in each successive operating cycle. The decrease

in càpacity was attributed to organic molecules in water which enter

the pores of the anion resin and are retained because of the affinity

they have with the ion exchange sites. Normal regeneration techniques

and rinse requirements do not allow sufficient time for removal of the

organic substances because of unfavorable conditions within the resin.

With the installation of the Dowex 11 anion exchange resin

ahead of the previous resin combination, the performance and water

quality of the system was greatly improved. The use of longer column

paths and special "screen" resins are recommended in the application

of ion exchange for oxidation pond effluents.

APPENDIX A

SUGGESTED OPERATING CONDITIONS FOR RESINS USED

55

DOWEX HGR-W

56

pH range

Max temperature

Min bed depth

Service flow rate

Backwash flow rate

Regenerant level

Regenerant concentration

Regenerant flow rate

Displacement rinse rate

Final rinse rate

Rinse requirement

0 - 14

300 °F

30 in.

2-4 gpm/cu ft (2)

8 gpm/sq ft

Dependent on capacity desired

2-87e H2 SO4

(67,)

0.5-2.0 gpm/cu ft (0.5)

Equal to regeneration rate

Equal to service rate

40-100 gal/cu ft (100)

Indicates actual rates used during this study

AMBERLITE XE-258

57

pH range

Max temperature

Minimum bed depth

Service flow rate

Backwash flow rate

Regenerant level

Regenerant concentration

Regenerant flow rate

Displacement rinse rate

Final rinse rate

Rinse requirement

0 - 14

100 °F

24 in.

1-3 gpm/cu ft (2)

507e expansion

Dependent on capacity desired

4% NaOH

0.5 gpm/cu ft (0.5)

0.5 gpm/cu ft

1.5 gpm/cu ft

About 25 gal/cu ft (25)

) Indicates actual rates used during this study

DOWEX 11

58

pH range

Max temperature

Minimum bed depth

Service flow rate

Backwash flow rate

Regenerant level

Regenerant concentration

Regenerant flow rate

Displacement rinse rate

Final rinse rate

Rinse requirement

0-14

140 °F

30 in.

2.0 gpm/cu ft (2)

Sufficient to produce at least507 expansion in bed volume

Dependent on capacity desired

4% NaOH

0.25-1.0 gpm/cu ft (0.5)

Same as regenerant rate

Approx. 1 gpm/cu ft

Approx. 50 gal/cu ft (50)

) Indicates actual rates used during this study

APPENDIX B

RESULTS OF ANALYSES PERFORMED DURING PHASE 1 AND PHASE 2

59

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REFERENCES

1. Fair, G. M., and Geyer, J. C., Water Supply and Waste Water Dis-posal, John Wiley and Sons, Inc., New York, 1967.

2. Warrington, S. L., "Effects of Using Lagooned Sewage Effluent onFarmland," Sewage Works Journal, 24, 1243 (1952).

3. Dow Chemical Company, Dowex Ion Exchange, Dow Chemical Co., Mid-land, Michigan (1964).

4. Ward, R. F., and Edgerly, E., Jr., "Organic Fouling of Anion Ex-change Resins," Environmental and Sanitary Engineering Laborator-ies, Washington University, St. Louis, Missouri (1965).

5. Anonymous, "Ion Exchange Resins Due for Sales Growth," Chemicaland Engineering News, 40, 34 (1962).

6. Morrison, W. S., and Tompson, J., "Twenty Years' Progress in IonExchange," Water and Sewage Works, 107, 225 (1960).

7. Klumb, G. H., "Control of Bacterial Reproduction in Cation ExchangeLayers," Jour. Amer. Water Works Assoc., 41, 933 (1949).

8. Wirth, L. F., "Effects of Oxidants on Ion Exchange," Industrial andEngineering Chemistry, 53, 638 (1961).

9. Bacon, H. E., and Lewis, W. J., "Interference of the Organic Con-taminants with the Ion Exchange Process," Combustion, 32, 153(1960).

10. Frish, N. W., and Kunin, R., "Organic Fouling of Anion ExchangeResins," Jour. Amer. Water Works Assoc., 52, 875 (1960).

11. Horembala, L. E., and Feldt, C. A., "Ion Exchange Screens," Power,112, 67 (May, 1968).

12. Sawyer, C. N., and McCarty, P. L., "Chemistry for Sanitary Engin-eers," 2nd Ed., McGraw-Hill Book Co., New York (1970).

13. Nalco Chemical Co., Dowex Ion Exchange Resins, Chicago, Ill.,

(1970).

14. Standard Methods for the Examination of Water Sewage and Indus-trial Wastes, 12th Ed., Amer. Pub. Health Assoc., New York 1965).

70

71

15. McKee, J. E., and Wolf, H. W., Water Quality Criteria, State WaterQuality Control Board, Sacramento, Calif. (1969).

16. Ahlgren, R. M., "Membrane vs. Resinous Ion Exchange Demineraliza-tion," Industrial Water Engineering, 8, 1, 12 (1971).

17. Oil, Paint, and Drug Reporter, "The Chemical Marketing Newspaper,"Schnell Publishing Company, Inc. (May, 1971).